1. Field of the Invention
The invention generally relates to a method of recognizing a track pitch of an optical disk, and more particularly to a method of recognizing the track pitch of the optical disk requiring one tracking operation.
2. Description of Related Art
The optical disk has become a popular storage medium due to its large storage capacity. Likewise, optical disk players for reading and writing optical disks have become indispensable in consumer computing and home entertainment devices (e.g., in music and speaker systems, and in digital players).
A surface of an optical disk has data tracks for storing data, and the data tracks are presented in a spiral shape, circling from an inner position of the optical disk outward. The data tracks have a plurality of data sectors, and each of the data sectors has an unique data sector address for recognition. The data sector addresses are disposed by accumulation coding from an inner position on the optical disk outward. In some conventional optical disks, the standard track pitch is decreased in order to expand the storage capacity of the optical disk. On the other hand, an optical disk player has an optical pickup head to access the data on the data tracks. Please refer to FIG. 1, which is a schematic view of a conventional optical disk player system. A spindle motor 120 is configured to rotate an optical disk 110, and an optical pickup head 140 is configured to read a data sector on a track. When the optical disk player performs a long distance track search, a sled motor 130 can be used to spin a screw 150 to drive the optical pickup head 140 from a current position D to a position E on a target track.
Since a distance between position D and position E is equivalent to a number of tracks therebetween multiplied by the track pitch, the optical disk player can calculate beforehand a required move distance, then employ the sled motor 130 to drive the optical pickup head 140. However, since there may be various types and configurations of optical disks, the track pitch thereof are different. When calculating the move distance of the optical pickup head, an overshoot or an undershoot of a read distance can result if an incorrect track pitch is used, and the optical pickup head 140 cannot be rapidly driven to position E. For example, when a track pitch of 1.6 μm for a standard Compact Disc (CD) is used to perform a tracking computation of a CD-Recordable (CD-R) having a track pitch of 1.4 μm, since the track pitch of the standard CD is larger, an issue of an overshooting move distance being generated results. Hence, track pitch detection significantly impacts a long distance target track seeking.